Clarify active stress comment wording in Integrator predictor

[Copilot]

This addresses a single PR review comment requesting an exact wording fix in Integrator.cpp. The intent is to correct grammar and make the comment read as “active stress model” without changing behavior.

• Targeted review-comment update

  • Updated one inline comment in Code/Source/solver/Integrator.cpp to replace “active stres/active stress” phrasing with clearer wording: “an active stress model is enabled.”
  • No logic or control-flow changes.

• Scope

  • Change is limited to the referenced review comment location (discussion_r3824124204) and does not touch other review threads.

// through all domains of all equations until we find one for which an active
// stress model is enabled.